CROSS-REFERENCE TO RELATED APPLICATIONS
TECHNICAL FIELD
[0002] Embodiments of the subject matter described herein relate generally to fluid infusion
devices for delivering a medication fluid to the body of a user. More particularly,
embodiments of the subject matter relate to the use of a gas trapping filter in the
medication fluid flow path.
BACKGROUND
[0003] Certain diseases or conditions may be treated, according to modern medical techniques,
by delivering a medication fluid or other substance to the body of a patient, either
in a continuous manner or at particular times or time intervals within an overall
time period. For example, diabetes is commonly treated by delivering defined amounts
of insulin to the patient at appropriate times. Some common modes of providing insulin
therapy to a patient include delivery of insulin through manually operated syringes
and insulin pens. Other modern systems employ programmable fluid infusion devices
(e.g., continuous insulin infusion devices such as insulin pumps) to deliver controlled
amounts of insulin or other drugs to a patient.
[0004] A fluid infusion device suitable for use as an insulin pump may be realized as an
external device or an implantable device, which is surgically implanted into the body
of the patient. External fluid infusion devices include devices designed for use in
a generally stationary location (for example, in a hospital or clinic), and devices
configured for ambulatory or portable use (to be carried by a patient). External fluid
infusion devices may establish a fluid flow path from a fluid reservoir to the patient
via, for example, a suitable hollow tubing. The hollow tubing may be connected to
a hollow fluid delivery needle that is designed to pierce the patient's skin to deliver
an infusion fluid to the body. Alternatively, the hollow tubing may be connected directly
to the patient's body through a cannula or set of micro-needles.
[0005] It is desirable to reduce the amount of air bubbles in a medication fluid before
delivering the fluid to the patient. Small bubbles may be introduced into the medication
fluid during a reservoir filling operation, for example, when the fluid reservoir
is filled from a vial using a syringe. Although patients are instructed to eliminate
air from a filled reservoir, some micro bubbles may remain.
[0006] Accordingly, it is desirable to have an assembly, system, or component that is designed
to mitigate the effects of air bubbles within a medication fluid flow path. In addition,
it is desirable to have an assembly, system, or component that reduces the presence
of air bubbles in a fluid flow path while also filtering particulates and/or unwanted
substances from the medication fluid. Furthermore, other desirable features and characteristics
will become apparent from the subsequent detailed description and the appended claims,
taken in conjunction with the accompanying drawings and the foregoing technical field
and background.
BRIEF SUMMARY
[0007] Disclosed herein is a fluid conduit assembly for delivery of a medication fluid.
An exemplary embodiment of the fluid conduit assembly includes a structure defining
a flow path for the medication fluid and a gas trapping filter coupled to the structure.
The gas trapping filter is positioned in the flow path to filter particulates from
the medication fluid and retain gas bubbles from the medication fluid.
[0008] A fluid delivery system is also disclosed herein. An exemplary embodiment of the
system includes: a fluid infusion pump to provide a medication fluid; a fluid conduit
assembly coupled to the fluid infusion pump; and a gas trapping filter. The fluid
conduit delivers the medication fluid to a user, and the fluid conduit assembly defines
a flow path for the medication fluid. The gas trapping filter is positioned in the
flow path to filter particulates from the medication fluid and retain gas bubbles
from the medication fluid.
[0009] Also disclosed herein is a fluid conduit assembly for delivery of a medication fluid.
An exemplary embodiment of the fluid conduit assembly includes a body section to receive
a fluid reservoir, and a flow path defined in the body section. The flow path carries
fluid from the fluid reservoir when the body section is coupled to the fluid reservoir.
The fluid conduit assembly also has a length of tubing extending from the body section
and in fluid communication with the flow path. The length of tubing carries fluid
from the body section during a fluid delivery operation. The fluid conduit assembly
also has a partially or predominantly hydrophilic gas trapping filter positioned in
the flow path to filter particulates from the medication fluid and retain gas bubbles
from the medication fluid.
[0010] This summary is provided to introduce a selection of concepts in a simplified form
that are further described below in the detailed description. This summary is not
intended to identify key features or essential features of the claimed subject matter,
nor is it intended to be used as an aid in determining the scope of the claimed subject
matter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A more complete understanding of the subject matter may be derived by referring to
the detailed description and claims when considered in conjunction with the following
figures, wherein like reference numbers refer to similar elements throughout the figures.
FIG. 1 is a simplified block diagram representation of an embodiment of a fluid delivery
system;
FIG. 2 is a plan view of an exemplary embodiment of a fluid delivery system that includes
a fluid infusion device and an infusion set;
FIG. 3 is a perspective view of an exemplary embodiment of a fluid delivery system
that includes a fluid infusion device designed to be affixed to the skin of the user;
FIG. 4 is a schematic representation of a portion of a fluid conduit assembly;
FIG. 5 is an exploded and partially phantom view of a connector assembly suitable
for use with a fluid conduit;
FIG. 6 is an exploded perspective view of an embodiment of a fluid conduit assembly
that is realized as a cap for a fluid reservoir;
FIG. 7 is an exploded perspective view of another embodiment of a fluid conduit assembly
that is realized as a cap for a fluid reservoir;
FIG. 8 is a perspective view of an exemplary embodiment of a fluid reservoir cap;
FIG. 9 is a side view of the fluid reservoir cap shown in FIG. 8;
FIG. 10 is an exploded perspective view of the fluid reservoir cap shown in FIG. 8;
FIG. 11 is a top view of the fluid reservoir cap shown in FIG. 8;
FIG. 12 is a cross-sectional view of the fluid reservoir cap taken across line A-A
of FIG. 11;
FIG. 13 is a top perspective view of an exemplary embodiment of a fluid reservoir
cap having retaining features integrated therein for retaining a filter;
FIG. 14 is a top perspective view of another exemplary embodiment of a fluid reservoir
cap having retaining features integrated therein for retaining a filter;
FIG. 15 is a partially exploded perspective view of an exemplary embodiment of a fluid
reservoir cap having rectangular shaped filters; and
FIG. 16 is a top view of the fluid reservoir cap shown in FIG. 15.
DETAILED DESCRIPTION
[0012] The following detailed description is merely illustrative in nature and is not intended
to limit the embodiments of the subject matter or the application and uses of such
embodiments. As used herein, the word "exemplary" means "serving as an example, instance,
or illustration." Any implementation described herein as exemplary is not necessarily
to be construed as preferred or advantageous over other implementations. Furthermore,
there is no intention to be bound by any expressed or implied theory presented in
the preceding technical field, background, brief summary or the following detailed
description.
[0013] The subject matter described here relates to certain assemblies, components, and
features of a fluid infusion system of the type used to treat a medical condition
of a patient. The fluid infusion system is used for infusing a medication fluid into
the body of a user. The non-limiting examples described below relate to a medical
device used to treat diabetes (more specifically, an insulin pump), although embodiments
of the disclosed subject matter are not so limited. Accordingly, the medication fluid
is insulin in certain embodiments. In alternative embodiments, however, many other
fluids may be administered through infusion such as, but not limited to, disease treatments,
drugs to treat pulmonary hypertension, iron chelation drugs, pain medications, anti-cancer
treatments, medications, vitamins, hormones, or the like. Moreover, the gas trapping
filter described below could be utilized in the context of other fluid delivery systems
if so desired.
[0014] For the sake of brevity, conventional features and technologies related to infusion
system operation, insulin pump and/or infusion set operation, and other functional
aspects of the fluid infusion system (and the individual operating components of the
system) may not be described in detail here. Examples of infusion pumps and/or related
pump drive systems used to administer insulin and other medications may be of the
type described in, but not limited to,
United States patent numbers: 4,562,751;
4,678,408;
4,685,903;
5,080,653;
5,505,709;
5,097,122;
6,485,465;
6,554,798;
6,558,351;
6,659,980;
6,752,787;
6,817,990;
6,932,584; and
7,621,893; which are herein incorporated by reference.
[0015] FIG. 1 is a simplified block diagram representation of an embodiment of a fluid delivery
system 100, which can be utilized to administer a medication fluid such as insulin
to a patient. The fluid delivery system 100 includes a fluid infusion device 102 (e.g.,
an infusion pump) and a fluid conduit assembly 104 that is coupled to, integrated
with, or otherwise associated with the fluid infusion device 102. The fluid infusion
device 102 includes a fluid reservoir 106 or an equivalent supply of the medication
fluid to be administered. The fluid infusion device 102 is operated in a controlled
manner to deliver the medication fluid to the user via the fluid conduit assembly
104. Although not depicted in FIG. 1, the fluid delivery system 100 also includes
a gas trapping filter that is positioned in the fluid flow path. In certain embodiments,
the gas trapping filter is located within the fluid flow path defined by the fluid
conduit assembly 104.
[0016] The fluid infusion device 102 may be provided in any desired configuration or platform.
In accordance with one non-limiting embodiment, the fluid infusion device is realized
as a portable unit that can be carried or worn by the patient. In this regard, FIG.
2 is a plan view of an exemplary embodiment of a fluid delivery system 200 that includes
a portable fluid infusion device 202 and a fluid conduit assembly that takes the form
of an infusion set component 204. For this particular embodiment, the infusion set
component 204 can be coupled to the fluid infusion device 202 as depicted in FIG.
2. The fluid infusion device 202 accommodates a fluid reservoir (hidden from view
in FIG. 2) for the medication fluid to be delivered to the user.
[0017] The illustrated embodiment of the infusion set component 204 includes, without limitation:
a tube 210; an infusion unit 212 coupled to the distal end of the tube 210; and a
connector assembly 214 coupled to the proximal end of the tube 210. The fluid infusion
device 202 is designed to be carried or worn by the patient, and the infusion set
component 204 terminates at the infusion unit 212 such that the fluid infusion device
202 can deliver fluid to the body of the patient via the tube 210. The fluid infusion
device 202 may leverage a number of conventional features, components, elements, and
characteristics of existing fluid infusion devices. For example, the fluid infusion
device 202 may incorporate some of the features, components, elements, and/or characteristics
described in
United States Patent numbers 6,485,465 and
7,621,893, the relevant content of which is incorporated by reference herein.
[0018] The infusion set component 204 defines a fluid flow path that fluidly couples the
fluid reservoir to the infusion unit 212. The connector assembly 214 mates with and
couples to the neck region of the fluid reservoir, establishing the fluid path from
the fluid reservoir to the tube 210. The connector assembly 214 (with the fluid reservoir
coupled thereto) is coupled to the housing of the fluid infusion device 202 to seal
and secure the fluid reservoir inside the housing. Thereafter, actuation of the fluid
infusion device 202 causes the medication fluid to be expelled from the fluid reservoir,
through the infusion set component 204, and into the body of the patient via the infusion
unit 212 at the distal end of the tube 210. Accordingly, when the connector assembly
214 is installed as depicted in FIG. 2, the tube 210 extends from the fluid infusion
device 202 to the infusion unit 212, which in turn provides a fluid pathway to the
body of the patient. For the illustrated embodiment, the connector assembly 214 is
realized as a removable reservoir cap (or fitting) that is suitably sized and configured
to accommodate replacement of fluid reservoirs (which are typically disposable) as
needed.
[0019] FIG. 3 is a perspective view of another exemplary embodiment of a fluid delivery
system 300 that includes a fluid infusion device 302 designed to be affixed to the
skin of the user. The fluid infusion device 302 includes two primary components that
are removably coupled to each other: a durable housing 304; and a base plate 306.
The fluid infusion device 302 also includes or cooperates with a removable/replaceable
fluid reservoir (which is hidden from view in FIG. 3). For this particular embodiment,
the fluid reservoir mates with, and is received by, the durable housing 304. In alternate
embodiments, the fluid reservoir mates with, and is received by, the base plate 306.
[0020] The base plate 306 is designed to be temporarily adhered to the skin of the patient
using, for example, an adhesive layer of material. After the base plate is affixed
to the skin of the patient, a suitably configured insertion device or apparatus may
be used to insert a fluid delivery needle or cannula 308 into the body of the patient.
The cannula 308 functions as one part of the fluid delivery flow path associated with
the fluid infusion device 302. In this regard, the cannula 308 may be considered to
be one implementation of the fluid conduit assembly 104 shown in FIG. 1 (or a portion
thereof).
[0021] FIG. 3 depicts the durable housing 304 and the base plate 306 coupled together. For
this particular embodiment, the durable housing 304 contains, among other components,
a drive motor, a battery, a threaded drive shaft for the fluid reservoir, one or more
integrated circuit chips and/or other electronic devices (not shown). The durable
housing 304 and the base plate 306 are cooperatively configured to accommodate removable
coupling of the durable housing 304 to the base plate 306. The removable nature of
the durable housing 304 enables the patient to replace the fluid reservoir as needed.
[0022] The fluid delivery systems 200, 300 described here are merely two exemplary embodiments
that can include a fluid conduit assembly outfitted with a gas trapping filter. In
this regard, FIG. 4 is a schematic representation of a portion of a fluid conduit
assembly 400 having a gas trapping filter 402 positioned therein. It should be appreciated
that the fluid conduit assembly 400 has been simplified for ease of illustration.
In practice, the fluid conduit assembly 400 may be realized in any of the fluid delivery
systems described here, and/or in other fluid delivery systems not specifically described
in detail here. For example, the fluid conduit assembly 400 may be implemented as,
or form a part of, a fluid infusion set, a connector assembly, a fluid reservoir,
a fluid reservoir cap, a chamber or internal feature of an infusion pump, or the like.
[0023] The fluid conduit assembly 400 is suitably configured to accommodate the delivery
of a medication fluid such as insulin. The fluid conduit assembly 400 includes a structure
404 (or structures) defining a flow path 406 for the medication fluid. In FIG. 4,
the structure 404 is depicted in cross section, and it resembles a tube. Alternatively,
the structure 404 can be a section of a fluid connector (such as a two-part detachable
connector), an internal feature of an infusion device, a portion of a fluid reservoir
coupler, or the like. In certain embodiments, the structure 404 includes, forms a
part of, or is realized as a reservoir cap for a fluid infusion device (see FIG. 6).
In some embodiments, the structure 404 includes, forms a part of, or is integrated
with an infusion set for a fluid infusion device. In this regard, the gas trapping
filter 402 can be integrated with the delivery cannula hub or housing that is located
at or near the downstream end of the infusion set. In yet other embodiments, the structure
404 includes, forms a part of, or is realized as a fluid connector, such as a LUER
LOK fitting or connector. In certain embodiments, the structure 404 is implemented
as a feature of the fluid infusion device. These and other deployments of the fluid
conduit assembly 400 are contemplated by this disclosure, and the particular examples
presented here are not intended to be limiting or exhaustive.
[0024] The flow path 406 is defined by the interior space of the structure 404. The gas
trapping filter 402 may be coupled to the structure 404 and positioned in the flow
path 406 such that the medication fluid passes through the gas trapping filter 402
during fluid delivery operations. FIG. 4 depicts a straightforward scenario where
the gas trapping filter 402 physically obstructs the flow path 406, such that the
medication fluid is not diverted around the gas trapping filter 402. In other embodiments,
there can be additional fluid flow paths that allow some of the medication fluid to
bypass the gas trapping filter 402.
[0025] The gas trapping filter 402 is formed from a suitable material, composition, or element
such that the medication fluid can easily pass through the gas trapping filter 402
during fluid delivery operations. The gas trapping filter 402 can be formed from a
hydrophilic, semi-hydrophilic, partially hydrophilic, or predominantly hydrophilic
material. Although a truly hydrophilic material may be ideal, the material used for
the gas trapping filter 402 can be partially or predominantly hydrophilic while exhibiting
some amount of hydrophobicity. In practice, the gas trapping filter 402 can exhibit
up to fifty percent hydrophobicity without adversely impacting the desired performance.
For example, the gas trapping filter 402 may include or be fabricated from a hydrophilic
membrane, a hydrophilic sponge material, or a hydrophilic foam material. As explained
below, the gas trapping filter 402 also serves to filter particulates from the medication
fluid during fluid delivery operations. Accordingly, the gas trapping filter 402 has
a pore size that is small enough to inhibit the flow of particulates. In certain embodiments,
the pore size is within the range of about 0.45 to 5.00 microns, which is suitable
for most medical applications. Non-limiting examples of suitable materials for the
gas trapping filter 402 include: polyacrylate; polyurethane; nylon; cellulose acetate;
polyvinyl alcohol; polyethelene foam; polyvinyl acetate; polyester fiber felt; polyester
(PET); polysulfone; polyethyl sulfone; collagen; polycaprolactone; or the like. It
should be appreciated that the material or materials used to fabricate the gas trapping
filter 402 can be treated to enhance the hydrophilic characteristics if so desired.
In certain embodiments, the gas trapping filter 402 includes or is fabricated from
a polyvinyl alcohol composition having a pore size within the range of 0.1 mm to 5.0
mm, e.g., an average of about 0.35 millimeter or 350 microns.
[0026] One function of the gas trapping filter 402 is to inhibit the downstream flow of
air bubbles. Depending on the particular composition and configuration of the gas
trapping filter 402, air bubbles 410 (depicted as small circles in the flow path 406
upstream of the gas trapping filter 402) can be blocked by the gas trapping filter
402 and/or retained within the gas trapping filter 402 as the liquid medication flows
downstream. Thus, the gas trapping filter 402 may be realized as a gas impermeable
membrane or material that also exhibits good hydrophilic properties. In some embodiments,
the gas trapping filter 402 can be fabricated from material having micro-cavities
formed therein for trapping and retaining gas bubbles from the medication fluid. FIG.
4 illustrates a scenario where the air bubbles 410 are removed from the medication
fluid. Accordingly, no air bubbles 410 are present in the medication fluid that resides
downstream from the gas trapping filter 402.
[0027] Another benefit of the gas trapping filter 402 relates to the volume accuracy of
the fluid delivery system. In certain implementations, syringe pumps are calibrated
to deliver a specified volume in response to a controlled mechanical actuation (e.g.,
movement of the syringe plunger in response to controlled rotation of an electric
motor). Reducing or eliminating air from the fluid delivery path increases the accuracy
of the volume calibrations.
[0028] In certain embodiments, the gas trapping filter 402 also serves to filter particulates
from the medication fluid such that the particulate count of the downstream medication
fluid is reduced. As mentioned above, the material used to fabricate the gas trapping
filter 402 can be selected with a desired pore size to accommodate filtering of particulates
having an expected size.
[0029] In some embodiments, the gas trapping filter 402 also serves to absorb and/or adsorb
certain substances, chemicals, or suspended elements from the medication fluid. For
example, the gas trapping filter 402 may include material that is configured or treated
to absorb/adsorb lubricating or manufacturing oil that is associated with the manufacturing,
assembly, or maintenance of one or more components of the fluid delivery system. In
this regard, a fluid reservoir for insulin can be fabricated with a trace amount of
silicone oil that serves as a lubricant for the plunger of the reservoir. Accordingly,
the gas trapping filter 402 can include a material, layer, or treatment that reduces,
traps, or otherwise removes some or all of the silicone oil from the medication fluid
as it passes through the gas trapping filter 402.
[0030] In particular embodiments, the gas trapping filter 402 also serves as a drug depot
during operation of the fluid delivery system. To this end, the gas trapping filter
402 can include a drug, medicine, chemical, or composition impregnated therein (or
coated thereon, or otherwise carried by the gas trapping filter 402). A quantity of
the drug is released into the medication fluid as the fluid flows through the gas
trapping filter 402 during a fluid delivery operation. The wavy lines 414 in FIG.
4 schematically depict the drug after it has been released into the downstream medication
fluid. In practice, the drug carried by the gas trapping filter 402 will eventually
be depleted unless the gas trapping filter 402 or the fluid conduit assembly 400 is
replaced before depletion. The drug carried by the gas trapping filter 402 can be
selected to address the needs of the particular patient, fluid delivery system, medication
fluid, etc. In accordance with the exemplary insulin infusion system described here,
the gas trapping filter 402 is impregnated with a drug that treats the patient site
to extend the useful life of the fluid infusion set. For example, the gas trapping
filter 402 can be treated with an anticoagulant such as Heparin or Dextran. As another
example, the gas trapping filter 402 can be impregnated or infused with an anti-proliferative
drug such as Rapamycin. It should be appreciated that these examples are neither exhaustive
nor restrictive, and that the gas trapping filter 402 can be impregnated, treated,
or infused with any drug that may be appropriate and suitable for the particular medical
condition, fluid delivery system, or application.
[0031] Although FIG. 4 shows a single component that serves as the gas trapping filter 402,
an embodiment of the fluid conduit assembly 400 can utilize a plurality of physically
distinct elements that collectively function as the gas trapping filter 402. For example,
the gas trapping filter 402 can be fabricated from different materials that are selected
for their properties and characteristics (gas trapping, oil absorption, oil adsorption,
particulate filtering). Moreover, certain embodiments of the fluid delivery system
can be outfitted with multiple gas trapping filters located in different sections
of the fluid flow path. For example, one filter component can be positioned at or
near the fluid reservoir, and another filter component can be positioned at or near
the distal end of the fluid infusion set. These and other practical implementations
are contemplated by this disclosure.
[0032] As mentioned above, the fluid conduit assembly that carries the gas trapping filter
can be realized in a number of different forms. For example, the fluid conduit assembly
may include or be realized as a fluid connector, where the gas trapping filter is
integrated in the fluid connector. In this regard, FIG. 5 is an exploded and partially
phantom view of a fluid connector assembly 500 suitable for use with a fluid conduit
assembly. The illustrated embodiment of the fluid connector assembly 500 functions
to physically and fluidly couple an upstream section of tubing 502 to a downstream
section of tubing 504. The fluid connector assembly 500 includes a first connector
506 (which is physically and fluidly coupled to the upstream section of tubing 502)
that mates with a second connector 508 (which is physically and fluidly coupled to
the downstream section of tubing 504). The first connector 506 includes a hollow needle
510 that provides a fluid flow path from the upstream section of tubing 502. The second
connector 508 includes a septum 512 that receives the hollow needle 510 when the first
connector 506 engages the second connector 508. When the two connectors 506, 508 are
engaged and locked together, the medication fluid can flow from the upstream section
of tubing 502, through the hollow needle 510, and into the downstream section of tubing
504.
[0033] One or both of the connectors 506, 508 can be provided with a gas trapping filter
having the characteristics and functionality described previously. For this particular
embodiment, a unitary gas trapping filter 516 is integrated in the second connector
508. The gas trapping filter 516 is located within the body of the second connector
508, and it resides downstream from the septum 512. During a fluid delivery operation,
the medication fluid exits the hollow needle 510, enters the second connector 508
(e.g., into a space that is upstream from the gas trapping filter 516), and is forced
through the gas trapping filter 516 before it passes into the downstream section of
tubing 504. The gas trapping filter 516 may be fabricated from material or compositions
described above with reference to the gas trapping filter 402. In certain embodiments,
the gas trapping filter 516 includes or is fabricated from a polyvinyl alcohol composition
having a pore size within the range of 0.1 mm to 5.0 mm, e.g., an average of about
0.35 millimeter or 350 microns.
[0034] As another example, a fluid conduit assembly configured as described herein may include
or be realized as an infusion set for a fluid infusion pump, where the gas trapping
filter is integrated in the infusion set. In this regard, FIG. 6 is an exploded perspective
view of a fluid conduit assembly that is realized as a cap or a connector assembly
600 for a fluid reservoir. In this regard, the connector assembly 600 is generally
configured as described above for the connector assembly 214 shown in FIG. 2. Accordingly,
the connector assembly 600 may be provided as component of a disposable infusion set.
[0035] The illustrated embodiment of the connector assembly 600 generally includes, without
limitation: a body section 602; a flow path defined in the body section 602; a length
of tubing 604 extending from the body section 602; and a gas trapping filter 606.
FIG. 6 depicts the body section 602 separated into two constituent parts: a lower
body section 602a; and an upper body section 602b. The lower body section 602a can
be affixed to the upper body section 602b (for example, by sonic welding or using
an adhesive) after installing the gas trapping filter 606 into a retaining cavity
610 formed within the lower body section 602a. In alternative embodiments, the body
section 602 can be fabricated as a one-piece component by molding a suitable material
while encapsulating the gas trapping filter 606 inside the body section 602. The gas
trapping filter 606 may be fabricated from material or compositions described above
with reference to the gas trapping filter 402. In certain embodiments, the gas trapping
filter 606 includes or is fabricated from a polyvinyl alcohol composition having a
pore size within the range of 0.1 mm to 5.0 mm, e.g., an average of about 0.35 millimeter
or 350 microns.
[0036] The lower body section 602b is suitably configured to receive a fluid reservoir,
e.g., by a threaded engagement, a snap fit, tabs, or the like. The tubing 604 is physically
and fluidly coupled to the upper body section 602b such that the tubing 604 is in
fluid communication with the flow path. This allows the tubing 604 to carry fluid
from the body section 602 during a fluid delivery operation. The flow path, much of
which is hidden from view in FIG. 6, may be defined by: a hollow needle that penetrates
a septum of the fluid reservoir; an internal space, chamber, or conduit of the lower
body section 602a, which is upstream of the gas trapping filter 606; and an internal
space, chamber, or conduit 614 of the upper body section 602b, which is downstream
of the gas trapping filter 606. The flow path continues into the tubing 604, which
is connected to the upper body section 602b.
[0037] The gas trapping filter 606 is secured within the body section 602 such that it is
positioned in the flow path of the medication fluid. During a fluid delivery operation,
the medication fluid is forced out of the fluid reservoir and into the hollow needle
(not shown in FIG. 6). The distal end of the hollow needle terminates at a location
that is upstream of the gas trapping filter 606. This positioning ensures that the
medication fluid can be filtered and otherwise treated by the gas trapping filter
606 before it exits the connector assembly 600. As explained above, the gas trapping
filter 606 is suitably configured to reduce the amount of air bubbles in the downstream
medication fluid, and to reduce the amount of particulates in the downstream medication
fluid.
[0038] FIG. 7 is an exploded perspective view of another embodiment of a fluid conduit assembly
700 that is realized as a cap for a fluid reservoir. The assembly 700 shares some
elements and features with the assembly 600 and, therefore, common elements and features
will not be redundantly described here in the context of the assembly 700. As mentioned
previously, the connector assembly 700 may be provided as component of a disposable
infusion set.
[0039] The illustrated embodiment of the connector assembly 700 generally includes, without
limitation: a body section 602 (having a lower body section 602a and an upper body
section 602b); a venting membrane 702; a hollow needle 704; a gas trapping filter
706; and a membrane 708. These components can be assembled together in the manner
generally described above for the assembly 600.
[0040] The venting membrane 702 can be affixed to the upper interior surface of the lower
body section 602a such that the venting membrane 702 covers one or more vent holes
710 formed in the top portion of the lower body section 602a. The vent holes 710 facilitate
venting of the reservoir chamber that resides in the housing of the fluid infusion
device (see, for example, FIG. 2). The hollow needle 704 can be affixed to the lower
body section 602a such that the downstream end 712 of the hollow needle 704 resides
below or within the gas trapping filter 706 after the fluid conduit assembly 700 is
fabricated. The positioning of the downstream end 712 is important to ensure that
the medication fluid is forced through the gas trapping filter 706 during fluid delivery
operations. The membrane 708 can be affixed within a cavity formed in the upper body
section 602b (the cavity is hidden from view in FIG. 7). The membrane 708 is at least
partially hydrophilic to allow the medication fluid to pass during fluid delivery
operations. In certain embodiments, the membrane 708 has a smaller pore size than
the gas trapping filter 706. For example, the membrane 708 may have a pore size within
the range of about 0.1 µm to about 10 µm.
[0041] The gas trapping filter 706 is secured within the body section 602 such that it is
positioned in the flow path of the medication fluid. For the illustrated embodiment,
the gas trapping filter 706 may be positioned between the membrane 708 and the downstream
end 712 of the hollow needle 704. In certain embodiments, the gas trapping filter
706 is realized as a foam, sponge, or felt fiber composite material. Although not
always required, the material used for the gas trapping filter 706 may include, without
limitation: polyvinyl acetate (PVA); polyvinyl alcohol; polyester (PET); polycarbonate;
polyurethane; polyethyl sulfone; collagen; polycaprolactone; or any combination thereof.
In accordance with certain embodiments, a felt-based gas trapping filter 706 has a
pore size within the range of about one to 100 microns, and preferably within the
range of about 20 to 40 microns. In accordance with certain embodiments, a sponge-based
gas trapping filter 706 has a pore size within the range of about 20 to 1000 microns.
The gas trapping filter 706 may be fabricated from material or compositions described
above with reference to the gas trapping filter 402. In certain embodiments, the gas
trapping filter 706 includes or is fabricated from a polyvinyl alcohol composition
having a pore size within the range of 0.1 mm to 5.0 mm, e.g., an average of about
0.35 millimeter or 350 microns. Regardless of its composition and configuration, the
gas trapping filter 706 is suitably configured to reduce the amount of air bubbles
in the downstream medication fluid, and to reduce the amount of particulates in the
downstream medication fluid.
[0042] FIG. 8 is a perspective view of an exemplary embodiment of a fluid reservoir cap
800, FIG. 9 is a side view of the cap 800, FIG. 10 is an exploded perspective view
of the cap 800, FIG. 11 is a top view of the cap 800, and FIG. 12 is a cross-sectional
view of the cap 800 as taken along line A-A of FIG. 11. The cap 800 is similar to
the connector assembly 600 and the fluid conduit assembly 700 described above. The
cap 800, however, is fabricated with a one-piece primary body section rather than
an upper body section and a lower body section.
[0043] At least one suitably shaped, sized, and configured gas trapping filter 802 is retained
within a neck region 804 of the cap 800. For the illustrated embodiment, two gas trapping
filters 802 are stacked within the neck region 804. The illustrated embodiment of
the cap 800 also includes: a venting membrane 806; a hollow needle 808; and a membrane
810 (as described above for the other embodiments). The cap 800 also includes an insert
812 that is inserted into the neck region 804 (see FIG. 12). When the cap 800 is assembled,
the gas trapping filters 802 and the membrane 810 are located between an interior
base section of the neck region 804 and a bottom section of the insert 812.
[0044] The gas trapping filters 802 may be fabricated from material or compositions described
above with reference to the gas trapping filter 402. In certain embodiments, each
gas trapping filter 802 includes or is fabricated from a polyvinyl alcohol composition
having a pore size within the range of 0.1 mm to 5.0 mm, e.g., an average of about
0.35 millimeter or 350 microns. In certain embodiments, the membrane 810 has a smaller
pore size than the gas trapping filters 802. For example, the membrane 810 may have
a pore size within the range of about 0.1 µm to about 10 µm.
[0045] During manufacturing of the cap 800, the gas trapping filters 802 should be oriented
as shown in FIG. 12 - aligned with each other, and vertically stacked without any
gap between them. However, fabrication and assembly processes may cause one or both
gas trapping filters 802 to shake, vibrate, shift, rotate, move, or otherwise become
mis-oriented. To address this scenario, the cap 800 can be fabricated with integrated
retaining features that are shaped, sized, arranged, and otherwise configured to keep
the gas trapping filters 802 in a stationary position after they have been installed
within the neck region 804 of the cap 800. At least one retaining feature can be implemented
to inhibit movement, shifting, or dislodging of the gas trapping filters 802 within
the cap 800.
[0046] FIG. 13 is a top perspective view of an exemplary embodiment of a fluid reservoir
cap 900 having retaining features 902 integrated therein for retaining at least one
filter (not shown). For clarity and ease of illustration, the cap 900 is shown without
its associated filter(s), hollow needle, membrane, or insert. FIG. 13 depicts a hole
904 that accommodates the hollow needle and/or fluid flow. The hole 904 is formed
within the interior base section of the neck region 906 of the cap 900. For this particular
embodiment, the retaining features 902 are realized as two projections that extend
radially inward toward the hole 904, although only one projection or more than two
projections can be utilized. The projections are configured to compress a portion
of the filter(s) to retain the filter(s) in the desired position and/or to guide at
least one filter during assembly and/or to hold at least one filter in place after
assembly. The retaining features 902 may include ridges (as shown), nubs, and/or textured
surfaces that provide additional friction to hold the filter(s) when installed. The
shape, contour, and dimensions of the retaining features 902 may vary from one embodiment
to another, as appropriate for the particular shape, size, and configuration of the
cap 900 and the filter(s).
[0047] FIG. 14 is a top perspective view of another exemplary embodiment of a fluid reservoir
cap 1000 having retaining features 1002 integrated therein for retaining at least
one filter (not shown). For clarity and ease of illustration, the cap 1000 is shown
without its associated filter(s), hollow needle, membrane, or insert. FIG. 14 depicts
a hole 1004 that accommodates the hollow needle. The hole 1004 is formed within the
interior base section of the neck region 1006 of the cap 1000. For this particular
embodiment, the retaining features 1002 are realized as three narrow block-shaped
projections that extend radially inward toward the hole 1004, although only one projection
or more than two projections can be utilized. The retaining features 1002 may include
ridges, nubs, and/or textured surfaces that provide additional friction to hold the
filter(s) when installed. The shape, contour, and dimensions of the retaining features
1002 may vary from one embodiment to another, as appropriate for the particular shape,
size, and configuration of the cap 1000 and the filter(s).
[0048] FIG. 15 is a partially exploded perspective view of an exemplary embodiment of a
fluid reservoir cap 1100 having rectangular shaped gas trapping filters 1102, and
FIG. 16 is a top view of the fluid reservoir cap 1100. As explained above with reference
to FIGS. 8-12, the cap 1100 includes an insert 1104 that retains the gas trapping
filters 1102 inside a neck region 1106 of the cap 1100.
[0049] The gas trapping filters 1102 may be fabricated from material or compositions described
above with reference to the gas trapping filter 402. In certain embodiments, each
gas trapping filter 1102 includes or is fabricated from a polyvinyl alcohol composition
having a pore size within the range of 0.1 mm to 5.0 mm, e.g., an average of about
0.35 millimeter or 350 microns.
[0050] FIG. 16 is a top perspective view of the cap 1100. For clarity and ease of illustration,
FIG. 16 depicts the cap 1100 without its associated filter(s), hollow needle, membrane,
or insert. FIG. 16 depicts a hole 1110 that accommodates the hollow needle and/or
fluid flow. The hole 1110 is formed within the interior base section of the neck region
1106 of the cap 1100. For this particular embodiment, a retaining feature 1114 for
the filter(s) is realized as a rectangular-shaped cavity that is shaped and sized
to match the outer dimensions of the filter(s). The cavity is defined by four sidewalls
that extend to support the outer walls of the filter(s) when the cap 1100 is assembled.
The sidewalls hold the filter(s) in position and inhibit rotation of the filter(s).
The sidewalls may include ridges, nubs, and/or textured surfaces that provide additional
friction to hold the filter(s) when installed. The shape, contour, and dimensions
of the cavity may vary from one embodiment to another, as appropriate for the particular
shape, size, and configuration of the cap 1100 and the filter(s).
[0051] While at least one exemplary embodiment has been presented in the foregoing detailed
description, it should be appreciated that a vast number of variations exist. It should
also be appreciated that the exemplary embodiment or embodiments described herein
are not intended to limit the scope, applicability, or configuration of the claimed
subject matter in any way. Rather, the foregoing detailed description will provide
those skilled in the art with a convenient road map for implementing the described
embodiment or embodiments. It should be understood that various changes can be made
in the function and arrangement of elements without departing from the scope defined
by the claims, which includes known equivalents and foreseeable equivalents at the
time of filing this patent application.
[0052] A fluid delivery system and a fluid conduit assembly suitable for use with the system
are disclosed herein. The system includes a fluid infusion pump and a fluid conduit
assembly coupled to the pump to deliver medication fluid to a user. The fluid conduit
assembly includes a structure defining a flow path for the medication fluid, and a
gas trapping filter coupled to the structure and positioned in the flow path. The
gas trapping filter functions to filter particulates from the medication fluid and
retain gas bubbles from the medication fluid. The structure includes at least one
retaining feature to inhibit movement of the gas trapping filter.
[0053] Further disclosed herein is the subject matter according to the following clauses:
- 1. A fluid conduit assembly for delivery of a medication fluid, the fluid conduit
assembly comprising:
a structure defining a flow path for the medication fluid;
a gas trapping filter coupled to the structure and positioned in the flow path to
filter particulates from the medication fluid and retain gas bubbles from the medication
fluid; and
at least one retaining feature to inhibit movement of the gas trapping filter within
the structure.
- 2. The fluid conduit assembly of clause 1, wherein the gas trapping filter comprises
a partially hydrophilic sponge, felt, or fiber composite material.
- 3. The fluid conduit assembly of clause 1 or of any of the preceding clauses, wherein
the structure comprises a reservoir cap for a fluid infusion device.
- 4. The fluid conduit assembly of clause 1 or of any of the preceding clauses, wherein
the structure comprises an infusion set for a fluid infusion device.
- 5. The fluid conduit assembly of clause 1 or of any of the preceding clauses, wherein
the structure comprises a fluid connector.
- 6. The fluid conduit assembly of clause 1 or of any of the preceding clauses, wherein
the structure comprises a feature of a fluid infusion device.
- 7. The fluid conduit assembly of clause 1 or of any of the preceding clauses, wherein
the at least one retaining feature comprises at least one projection integrally formed
in the structure, the at least one projection configured to compress a portion of
the gas trapping filter.
- 8. The fluid conduit assembly of clause 1 or of any of the preceding clauses, wherein
the at least one retaining feature includes ridges, nubs, and/or textured surfaces
to provide additional friction to hold the gas trapping filter in place.
- 9. The fluid conduit assembly of clause 1 or of any of the preceding clauses, wherein
the at least one retaining feature comprises a cavity integrally formed in the structure,
the cavity shaped and sized to match outer dimensions of the gas trapping filter.
- 10. The fluid conduit assembly of clause 9 or of any of the preceding clauses, wherein:
the gas trapping filter has a rectangular block shape; and
the cavity is rectangular-shaped to accommodate the rectangular block shape of the
gas trapping filter.
- 11. The fluid conduit assembly of clause 10 or of any of the preceding clauses, wherein
sidewalls of the cavity include ridges, nubs, and/or textured surfaces to provide
additional friction to hold the gas trapping filter in place.
- 12. A fluid delivery system comprising:
a fluid infusion pump to provide a medication fluid;
a fluid conduit assembly coupled to the fluid infusion pump to deliver the medication
fluid to a user, the fluid conduit assembly defining a flow path for the medication
fluid;
a gas trapping filter positioned in the flow path to filter particulates from the
medication fluid and retain gas bubbles from the medication fluid; and
at least one retaining feature to inhibit movement of the gas trapping filter within
the flow path.
- 13. The fluid delivery system of clause 12, wherein:
the fluid conduit assembly comprises a reservoir cap for the fluid infusion pump;
and
the gas trapping filter is integrated in the reservoir cap.
- 14. The fluid delivery system of clause 12 or 13, wherein:
the fluid conduit assembly comprises an infusion set for the fluid infusion pump;
and
the gas trapping filter is integrated in the infusion set.
- 15. The fluid delivery system of clause 12 or of any of the clauses, wherein 12 to
14:
the fluid conduit assembly comprises a fluid connector; and
the gas trapping filter is integrated in the fluid connector.
- 16. A fluid delivery system, a fluid conduit, or a fluid reservoir cap having any
or all of the features shown and described herein.
- 17. A component of a medication fluid delivery system, the component comprising a
fluid filter retained in a neck region, and the component further comprising at least
one retaining feature to inhibit movement of the fluid filter within the neck region.
- 18. The component of clause 17, wherein the at least one retaining feature has any
or all of the features shown and described herein.
1. A fluid conduit assembly for delivery of a medication fluid, the fluid conduit assembly
comprising:
a structure defining a flow path for the medication fluid;
a gas trapping filter coupled to the structure and positioned in the flow path to
filter particulates from the medication fluid and retain gas bubbles from the medication
fluid; and
at least one retaining feature to inhibit movement of the gas trapping filter within
the structure.
2. The fluid conduit assembly of claim 1, wherein the gas trapping filter comprises a
partially hydrophilic sponge, felt, or fiber composite material.
3. The fluid conduit assembly of one of the claims 1 or 2, wherein the structure comprises
a reservoir cap for a fluid infusion device, and/or wherein the structure comprises
an infusion set for a fluid infusion device.
4. The fluid conduit assembly of one of the claims 1 to 3, wherein the structure comprises
a fluid connector.
5. The fluid conduit assembly of one of the claims 1 to 4, wherein the structure comprises
a feature of a fluid infusion device.
6. The fluid conduit assembly of one of the claims 1 to 5, wherein the at least one retaining
feature comprises at least one projection integrally formed in the structure, the
at least one projection configured to compress a portion of the gas trapping filter.
7. The fluid conduit assembly of one of the claims 1 to 6, wherein the at least one retaining
feature includes ridges, nubs, and/or textured surfaces to provide additional friction
to hold the gas trapping filter in place.
8. The fluid conduit assembly of one of the claims 1 to 7, wherein the at least one retaining
feature comprises a cavity integrally formed in the structure, the cavity shaped and
sized to match outer dimensions of the gas trapping filter.
9. The fluid conduit assembly of one of the claims 1 to 8, wherein:
the gas trapping filter has a rectangular block shape; and
the cavity is rectangular-shaped to accommodate the rectangular block shape of the
gas trapping filter,
particularly wherein sidewalls of the cavity include ridges, nubs, and/or textured
surfaces to provide additional friction to hold the gas trapping filter in place.
10. A fluid delivery system comprising:
a fluid infusion pump to provide a medication fluid;
a fluid conduit assembly coupled to the fluid infusion pump to deliver the medication
fluid to a user, the fluid conduit assembly defining a flow path for the medication
fluid;
a gas trapping filter positioned in the flow path to filter particulates from the
medication fluid and retain gas bubbles from the medication fluid; and
at least one retaining feature to inhibit movement of the gas trapping filter within
the flow path.
11. The fluid delivery system of claim 10, wherein:
the fluid conduit assembly comprises a reservoir cap for the fluid infusion pump;
and
the gas trapping filter is integrated in the reservoir cap.
12. The fluid delivery system of one of the claims 10 or 11, wherein:
the fluid conduit assembly comprises an infusion set for the fluid infusion pump;
and
the gas trapping filter is integrated in the infusion set.
13. The fluid delivery system of one of the claims 10 to 12, wherein:
the fluid conduit assembly comprises a fluid connector; and
the gas trapping filter is integrated in the fluid connector.
14. A fluid delivery system, a fluid conduit, or a fluid reservoir cap having any or all
of the features shown and described herein.
15. A component of a medication fluid delivery system, the component comprising a fluid
filter retained in a neck region, and the component further comprising at least one
retaining feature to inhibit movement of the fluid filter within the neck region,
particularly wherein the at least one retaining feature has any or all of the features
shown and described herein.